mm of water to atmospheres
Convert mm of water to atmosphere — instant, free, with the formula shown.
How to convert mm of water to atmosphere
To convert mm of water to atmosphere, multiply by 9.6784e-5:
For example, 10 mmH₂O × 9.6784e-5 = 0.000968 atm.
mmH₂O to atm conversion table
| mm of water (mmH₂O) | atmospheres (atm) |
|---|---|
| 1 mmH₂O | 9.6784e-5 atm |
| 2 mmH₂O | 0.000194 atm |
| 5 mmH₂O | 0.000484 atm |
| 10 mmH₂O | 0.000968 atm |
| 25 mmH₂O | 0.00242 atm |
| 50 mmH₂O | 0.004839 atm |
| 100 mmH₂O | 0.009678 atm |
| 250 mmH₂O | 0.024196 atm |
| 500 mmH₂O | 0.048392 atm |
| 1000 mmH₂O | 0.096784 atm |
Other mm of water conversions
Convert to atmosphere from another unit
mmH₂O to atm — frequently asked
How many atmospheres are in 1 mm of water?
1 mm of water = 9.6784e-5 atmospheres (mmH₂O × 9.6784e-5 = atm).
What is the formula to convert mm of water to atmosphere?
Multiply your mm of water value by 9.6784e-5 to get atmosphere.
How do I convert 10 mm of water to atmospheres?
10 mmH₂O = 0.000968 atm. For 100 mmH₂O the answer is 0.009678 atm. Use the calculator on this page for any other value.
When to convert mm of water to atmosphere
Pressure conversion — common questions
What's the difference between bar and psi?
1 bar = 100,000 Pa ≈ 14.504 psi. Bar is metric/SI-friendly; psi is US imperial. Tire pressure in cars is commonly 30–35 psi or ≈ 2.1–2.4 bar.
Is 1 atmosphere the same as 1 bar?
Very close but not identical. 1 atm = 1.01325 bar = 101,325 Pa. 1 bar = 100,000 Pa.
Why is blood pressure in mmHg?
Historically measured with mercury manometers — the pressure that supports a column of mercury that many millimetres tall. 120 mmHg systolic ≈ 16 kPa.